The overall capacities of communications systems, such as satellite systems, are increasing exponentially, and such capacity increases present unique challenges in the associated system and network designs. As one example, the overall capacities of broadband satellites are increasing exponentially, and the goal of the system designers, system operators, and service providers is to support and provide efficient, robust, reliable and flexible services, in a shared bandwidth network environment, utilizing such high capacity satellite systems. In current systems, for example, where multiple remote nodes are capable of accessing a public network (e.g., the Internet) or a remote network through one or more aggregation nodes, transmission of data and information by a plurality of terminals at a given time can thus create challenges and inefficiencies in network management, especially where system loads dynamically change over given periods of time.
For example, in communications networks with long round trip time (RTT), the random access channel (for example, the Aloha channel) can also be used for transmitting data with stringent latency requirement, such as control message, real-time and interactive traffic. As an example, in the inroute (the direction from a remote terminal to the gateway) of the satellite network, the high priority traffic can be sent via the random access channels to avoid large latency due to the delay of TDMA slot allocation. Because of the innate collision characteristics of a random access channel, when the throughput increases, the collision rate of the random access channels also becomes higher, resulting in unwanted retransmissions which in turn bring increased latency in the transmission.
In common practice, there exists a mechanism which backs off the transmission time once a collision happens. It has a drawback that a terminal starts to take preventive action (i.e., back-off) only after a collision. In addition, the back-off time increases as more collisions occur. Therefore, such a legacy approach may not be efficient or even suitable when high priority traffic with stringent latency requirements is using random access channels, particularly when a lot of such traffic is queued for transmission. Similar concerns can exist in other types of communications systems. Accordingly, current systems fail to support efficient, robust, reliable and flexible transmission services, particularly in shared bandwidth network environments, such as those utilizing such high capacity satellite systems.
For example, a prior known Aloha algorithm in a TDMA system typically has a long latency and underperformed throughput when the traffic load is high due to the method of self-detecting collision. In communications networks with long round trip time (RTT), the random access channel (for example, the Aloha channel) can also be used for transmitting data with stringent latency requirement, such as control message, real-time and interactive traffic. As an example, in the inroute (the direction from a remote terminal to the gateway) of the satellite network, the high priority traffic can be sent via random access channels to avoid large latency due to the delay of TDMA slot allocation. Because of the innate collision characteristics of a random access channel, when the throughput increases, the collision rate of random access channels also becomes higher, resulting in unwanted retransmissions which in turn bring increased latency in the transmission. A practical understanding is that when using Aloha type random access channels, there is a need for a desired throughput that corresponds to an acceptable operating collision rate.
In common practice, there exists a mechanism which backs off the transmission time once a collision happens. It has a drawback that a terminal starts to take preventive action (i.e., back-off) only after a collision. In addition, the back-off time increases as more collisions occur. Therefore, such a legacy approach may not be efficient or even suitable when high priority traffic with stringent latency requirements is using random access channels, particularly when a lot of such traffic is queued for transmission.
Thus, achieving efficient, robust, flexible and fast broadband services, in such a high capacity, shared bandwidth, satellite system network, however, poses unique challenges to system designers and operators to provide improved latency and throughput performance. In this regard, design challenges exist in ensuring that a remote node or terminal can efficiently identify in real time available transmission opportunities with a transmission probability capable of providing the required services for data transmission, and ensuring that load balancing is dynamically employed across one or more transmission channels for a plurality of remote terminals or nodes.
What is needed, therefore, is a system design that employs a dynamic and flexible architecture and method for determining a real time throughput of communications channels in a communications system and transmitting or providing such determined throughput to a plurality of terminals to enhance and provide efficient, robust, reliable and flexible services in a high capacity, shared network, such as in a high capacity, shared bandwidth, satellite network, and that would be relatively efficient and automated from a network management and load balancing standpoint. Further, a communications system that can reduce dependence on or can reduce or effectively eliminate the need for the terminal to detect collisions in a transmission channel by itself and thus improves the latency performance for transmission of traffic over a communications channel, such as random access channel according to an Aloha or diversity aloha protocol is also needed.